1. Field of the Invention
This invention relates to a digital waveform synthesizer and more particularly to a synthesizer generating a waveform at a plurality of different frequencies from a single clock signal.
2. Description of the Prior Art
When a periodic waveform is synthesized as a plurality of discrete steps derived by repetitively counting a high frequency clock signal, the number of counts must be an integral number and the percentage error in the frequency of the synthesized waveform is reduced by increasing the count number. Thus, rounding a required count number of 50.5 to 50 produces a 1% error while rounding a required count number of 100.5 to 100 produces only a 0.5% error. The count number can be increased by increasing the clock signal frequency or decreasing the number of steps in one cycle of a synthesized waveform. However, practical restraints limit these parameters. Therefore, better frequency accuracy has heretofore required higher frequency counting circuits or lower quality synthesized waveforms.